Tracy Morgan explains Sundance collapse, sort of

What a deeply curious Tracy Morgan interview on "Late Show with David Letterman" last night! It wasn't exactly an interview, but one of those interactions (which Dave and the usually reliable Morgan do so well) in which soft balls are served, and guest shags 'em over the rightfield wall. The one clip CBS has posted from this encounter, which seemed to mystify both Dave and the audience, in which Morgan talks about the recent Sundance fainting spell...